Modifying hydrocarbon polymers with poly (diazo) compounds



United States Patent 3,274,166 MGDIFYING HYDROCARBON POLYMERS WITH POLYGDIAZO) 0MPOUNDS David S. Breslow and Harold M. Spurlin, Wilmington, DeL, assignors to Hercules incorporated, a corporation of Delaware No Drawing. a Filed June 19, 1963, Ser. No. 288,896

18 Claims. (Ci. 260-85.1)

This application is a continuation-in-part of application Serial No. 88,314, filed February 10, 1961, now abandoned.

This invention relates to modifying polymers and to the products so produced. More particularly, the invention relates to modifying hydrocarbon polymers with certain poly(diazo) compounds and to the products so produced.

In the past the rubber industry has depended almost entirely upon sulfur or sulfur-bearing materials as vulcanizing, i.e., cross-linking, agents. It has more recently been discovered that certain types of organic peroxides or azo compounds are capable of acting as vulcanizing agents. However, all of the above agents suffer the drawback that because of their mode of action they are not equally effective in cross-linking all types of hydrocarbon polymers. For example, polybutadiene is effectively vulcanized by peroxides while butyl rubber is not.

Now, in accordance with this invention, it has unexpectedly been found that any hydrocarbon polymer can be cross-linked with certain poly(diazo) compounds to produce vulcanizates that are tough, resilient, solvent resistant, and odor free. In addition, it has been found that the hydrocarbon polymers can be treated with smaller amounts of the poly(diazo) compounds to improve their properties without materially aifecting their solubility.

The poly(diazo) compounds useful in the process of this invention are selected from the group consisting of where x is an integer greater than 1, preferably from 2 to 100, R is an organic radical inert to modification reactions, A is an aromatic radical inert to modification reactions, R is a hydrogen, alkyl, aryl or COOZ radical where Z is an alkyl or aryl radical and R" is a hydrogen, alkyl or aryl radical. Exemplary of these poly(diazo) compounds are the bis(diazoacetate) ester of 1,6-hexanediol, the bis(diazoacetate) ester of 1,10-decanediol, the tris(diazoacetate) ester of trimethylolethane, the tetra (diazoacetate) ester of pentaerythritol, the bis(diazoacetate) ester of diethylene glycol, the bis(diazoacetate) ester of dioxyethylene sulfide, the bis(diazoacetate) ester of p-hydroxymethyl benzyl alcohol, the tris(ot-diazopropionate) ester of trimethylolmethane, the bis(a-diazopropionate) ester of 1,10-decanediol, the bis(ot-diazobutyrate) ester of 1,6-hexanediol, the bis(a-diazo-aphenylacetate) ester of 1,10-decanediol, the bis(a-diazoa-phenylacetate) ester of hydroquinone, the bis(diazo carbomethoxy acetate) ester of 1,4-butanediol, the bis (diazo carbophenoxy acetate) ester of 1,6-hexanediol, pbis(diazomethyl) benzene, m-bis(oc-diazoethyl) benzene, p bis(u diazobutyl) benzene, u,a' bis(diazo) oc,ot'- bis(phenyl) m xylene, a t bis(diazo) o e bis (carbomethoxy) p xylene, oc,oc' bis(diazo) 0t,a' bis (carbophenoxy) p xylene, p bis(diazoacetyl) benzene, rn bis(a diazopropionyl) benzene, 04,00 bis(diazo)- 02,00 bis(phenyl) p diacetylbenzene, etc. These poly (diazo) compounds can be prepared in various ways as, for example, by diazotizing the corresponding poly (amines).

Instead of using a free poly(diazo) compound as the modifying agent, a precursor that will form one of the above-defined poly(diazo) compounds under conditions of the modification reaction can be used to advantage, particularly in the case where the free diazo compound is unstable. Exemplary precursors are the nitrosoureas, nitrosourethanes, N nitroso derivatives of rnesityl oxideamine adducts, sulfonamides and bis-toluenesulfonohydrazones which have the formulae:

where B is selected from the group consisting of R 0 0 R R R 'i o R o tl 'JH A H* and R O 0 R walla-1L5 where R, R, A and R" are as defined above, W is hydrogen or a phenyl radical, and Y is an organic radical. Exemplary of these precursors are N,N'-dinitroso-N,N-dicarbamyl-1,6-hexanedio1 diglycinate, m-bis(N-nitroso-N-carbamyl-aminomethyl) benzene, p-bis(N-nitrosoN-carbamyl-aminoacetyl) benzene, N,N'-dinitroso-N,N-dicarbethoxy-1,6-hexanediol diglycinate, p-bis(N-nitrosoN-carbethoxy-aminomethyl) benzene, m-bis(N-nitroso-N-carbophenoxy-aminoacetyl) benzene, 1,10-decanediol-bis [N-nitroso-N-(4-keto-2-methyl- Z-pentyl) glycinate], N,N'-dinitroso-N,N-di-p-toluenesulfonyl-1,6-hexanediol diglycinate, m-bis(N-nitroso-N-benzenesulfonyl-aminomethyl) benzene, p-bis(N-nitrosoN-benzenesulfonylaminoacetyl) benzene, terephthalaldehyde-bis (p-toluene sulfonohydrazone) m-dibenzoylbenzene bis (p-toluenesulfono-hydrazone), etc.

The above-mentioned precursors will readily form poly(diazo) compounds when treated with a base. Exemplary bases which can be used to convert the precursors are the alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, etc.; the alkali metal alkoxides such as lithium ethoxide, sodium rnethoxide, potassium tert-butoxide, etc.; and certain alkaline metal oxides such as magnesium oxide, zinc oxide, etc. In general, the base Will be used in an amount of from about 1 to about 200 mole percent based on the precursor.

Unlike azo compounds which upon heating produce a free radical, diazo compounds liberate nitrogen and produce a carbene, i.e., a carbon containing a sextet of electrons. Therefore, it is believed that the poly(diazo) compounds react by eliminating nitrogen, leaving a carbene group at each end of the molecule. These free carbene groups then react with carbon groups in the hydrocarbon polymer. If the hydrocarbon polymer is saturated, the following type of bond may be formed:

cross-linking or other modification is effected by irradiation, additives should be used in amounts which do not inhibit the passage of the radiation. Obviously, there R R l are many cases in which an additive is not required or g g 5 desired and excellent results are achieved when only the poly(diazo) compound is added. where R and R are as described above. If the hydro- The following examples are presented for purposes carbon polymer is unsaturated, the following type of of illustration, parts and percentages being by weight bond may be formed: unless otherwise specified.

The extent to which the polymers are cross-linked is g indicated by the percent gain in insolubility in solvents in which the uncross-linked polymer was soluble, hereinafter termed percent gel. Percent gel is determined as follows: A weighed sample of polymer is soaked in hot g g toluene for a specified length of time. The sample is then removed and dried to constant weight. The weights Where R and e as descflbed aboveof initial and final sample are corrected for polymer and From the above It can be 86611 that y yl of hydrocopolymer content based on knowledge of components. ctllrbon 11: 0l31;m1er, saturlated orlunsaturzttecz, as, fortexam- From these figures p e, po yet y ene, po ypropy ene, po ys yrene, s yrenebutadiene rubber, butyl rubber, natural rubber, polyw oo go] butadiene, polyisobutylene, ethylene-propylene copolycorrected lnltml welght mer, cis-l,4-polyisoprene, ethylene-propylene-dicyclopen- Example 1 tadiene terpolymer, etc., and blends of these polymers with each other can be modified with the above-defined Th1s example demonstrates the PtePatatlon of some poly(diazo) compounds -or their precursors. potymteze) eompounds- The modification can be carried out by either heating The btsmtazeaeetate) esters of e' e and the hydrocarbon polymer plus the poly(diazo) Compound 1 ,lO-decaned1ol were prepared by reacting glycinyl chloabove its decomposition temperature or by exposing the t hydt'eetttende t t mixture to ultraviolet radiation. Various amounts of the d101, respeettvely- The tntetmettlate dlammes were h poly(diazo) compound can be added, the optimum treated with aqueous sodium nitrite and 10% sulfuric amount depending on the amount of orosshnkhtg or acid in an ice bath and while under a layer of ether. other modification desired, the specific poly(diazo) come ether layer was P e waehed t 5% aqueous pound employed, etc In general the amount added sodium carbonate solution, dried with sodium sulfate, and (based on the Weight of the polymer) will be from b t n the ether removed under vacuum. The b1s(d1aZo- 0005170 to about 25%, most Preferably from about acetate) ester of 1,6-hexaned1ol produced was a pale 001% to about 20%, and more Preferably from about yellow 011 having a half-life of 16 mlnutes at a temperato about ture of 155 C. It was analyzed for percent carbon,

The modifying agent can be incorporated with the hydrogen, and nitrogen. The results of the analysis are mer in any desired fashion; for example, it can be uni- 40 gtven belowformly blended by simply milling on a conventional rub- Found: 46-55%; 55%; Calculated! ber mill. By this means the diaz-o compound is distrib- C, 471%} 55%; N, 22.0%. uted throughout the polymer and uniform cross-linking The blswtazoaeetatte) ester of llo'decanediol P or other modification is effected when the blend is either duced was a Yellow was analyzed for Percent subjected to heat or ultraviolet radiation. Other methods h e and nltrogenx The results of the of mixing the modifying agent with the polymer will be analysts are gtven belowabpareut to those Skilled in the art Found: C, 54.3%; H, 7.0%; N, 18.1%. Calculated:

The temperature at which modification is effected can C, 542%; 115%; N, 180%- be varied over a wide range. When cross-linking or other modification is eifec-ted by heating, the temperature will Examples 2 8 depend on the decomposition temperature of the poly The tWO biswtaloacetates) described in Example 1 (di compound or precursor, I general, h were used as cross-linking agents for various hydrocarbon perature will be in the range of from about 0 C. to Polymers y mixing Or the Other i h a lution of about 250 C. a polymer in a solvent, removing the solvent by evapora- In addition to the poly(diazo) compound, other in- 5 tiOIl, and then curing the P y by heating in an iron gredients can also be incorporated. The additives commold for a given length of time at a given temperaturemonly used in rubber vulcanizates can be used here also, The P y cross-linked, the Solvents in Which y as, for example, extenders, fillers, pigments, plasticizers, Were dissolved, the biS(diaZOatate) used, the Parts Of stabilizers, etc. Exemplary of the fillers that can be cross-linking agent per 100 parts of polymer, the temadded are calcium carbonate, iron oxide, carbon black, p ratllr and time Of curing, and the amount of crosssilica, calcium silicate (hydrated), alumina, etc. When linking (recorded as percent gel) are listed in Table 1.

TABLE 1 Example No. Polymer Cross-linking Agent Solvent crgg liiiiiing T311011?" 3 Agent/ Parts of Polymer 2 Naturalrubber Bis(diazoacetate)esterof1,6- Trichl0roethylene 3 180 20 9 an he tgnediol. do 5 1 r i: aaiylmpmpyienecopes: :::do 5.8 175-122 53 23 mer containing 32 mole percent propylene.

5, dn Bis(diazoacetate) ester of do 4.5 175-130 3 G6 1,10-decauediol.

6 o o 12 185 30 76 Naturalrubber "do"... d 5 25 95 Styrene-butadiene rubber do 5.9 -130 20 39 containing 25 mole percent styrene.

Example 9 Natural rubber (smoked sheet #1) was compounded with carbon black, stearic acid, zinc oxide, and the bis (diazoacetate) ester of 1,10-decanediol, described in Example l, on a 2-roll mill at 80 C. for 10 minutes and then heated at 175 C. for 30 minutes under a pressure of 1000 p.s.i. The composition used is tabulated below:

Composition: Parts Natural rubber 100 High abrasion furnace black 5O Stearic acid 1 Zinc oxide 5 Bis(diazoacetate) ester of 1,10-decanediol 5 The resulting vulcanizate was a strong, tough rubber.

Example 10 T 100 parts of styrene-butadiene copolymer (GRS 1500) were added 50 parts of high abrasion furnace black, 1 part of stearic acid, parts of zinc oxide, and 5 parts of the bis(diazoacetate) ester of 1,10-decanediol of Example 1. This mixture was blended on a 2-roll mill at 80 C. for minutes and then heated between steel plates at a temperature of 175 C. and a pressure of 1000 p.s.i. for 30 minutes. The resulting vulcanizate was a strong, tough rubber.

Example 11 To a slurry of high-density polyethylene in benzene was added suflicient solution of the bis(diazoacetate) ester of l,6 hexanediol, of Example 1, dissolved in benzene to make a slurry containing 3 parts of diazo compound per 100 parts of polymer. The slurry was dried overnight at room temperature and the resulting powder pressed between steel plates at a temperature of 175 C. and :a pressure of 1000 p.s.i. for 30 minutes. The film thus formed was substantially insoluble in hot decahydronaphthalene. The same procedure was carried out with polypropylene with the same results.

Examples 12 and J3 p-Bis(diazoacetyl) benzene was used in two compositions to cross-link ethylene-propylene copolymers.

Example 12: Parts Ethylene-propylene copolymer (32 mole percent propylene) 100 p-Bis(diazoacetyl) benzene 5 This composition was blended on a 2-roll mill at 80 C. and then cured for 60 minutes at 175 C. under 1000 p.s.i. pressure. The resulting vulcanizate was a strong, tough rubber, substantially insoluble in toluene.

Example 13: Parts Ethylene-propylene copolymer (33 mole percent propylene) 100 High abrasion furnace black 50 p-Bis(diazoacetyl) benzene 5 This composition was blended on a 2-roll mill at 80 C. and then cured between steel plates under a pressure of 1000 p.s.i. for 30 minutes at 175 C. The resulting vulcanizate was a tough, resilient rubber, substantially insoluble in toluene.

Example 14 The tris(diazoacetate) ester of trimethylolethane was prepared from trimethylolethane by the method described in Example 1. The resulting tris(diazo) compound was a yellow viscous oil.

Natural rubber was compounded with 5 parts per hundred of the above-described tris(diazo) compound on a 2-roll mill at 80 C. for 12 minutes. The composition was cured at a temperature of 180 C. for 25 minutes under a pressure of 1000 p.s.i. The resulting vulcanizate had a percent gel of 93.

6 Example 15 Meta-bis(a-diazoethyl) benzene, C H (CN CH was prepared by dissolving the bis(hydrazone) of mdiacetyl benzene in toluene, cooling in an ice bath, and then treating with yellow mercuric oxide.

The above bis(diazo) compound was used in the following composition to cross-link styrene-butadiene rubber (SBR):

Composition: Parts Styrene-butadiene rubber High abrasion furnace black 50 Stearic acid 1 Zinc oxide 5 m-Bis(a-diazoethyl) benzene 5 The resulting vulcanizate was a strong, tough rubber.

Example 16 This example illustrates the use of a bis-toluenesulfonohydrazone precursor in the cross-linking of an ethylenepropylene coplymer containing 32 mole percent propylene.

Terephthalaldehyde bis(p toluenesulfonohydrazone) was prepared by reacting terephthalaldehyde with p-toluenesulfonohydrazine in an aqueous hydrochloric acid medium.

A solution of 1 part of terephthalaldehyde bis(pt-oluenesulfonohydrazone) in dry dimethylformamide was prepared. To the ssolution was added 1.5 parts of potassium tert-butoxide and a bright yellow suspension formed. The suspension was added to a solution of the ethylene-propylene copolymer in toluene with vigorous agitation. The resulting suspension contained approximately 10 parts of the bis-toluenesulfonohydrazone per 100 parts of copolymer. The solvents were removed under vacuum and the resulting mixture was cured in a closed iron mold for 1 hour at a temperature of 177 C. The resulting vulcanizate had a percent gel of 96.

Examples 17 and 18 These examples illustrate the use of dilferent bis-toluenesulfonohydrazones) in the cross-linking of a styrenebutadiene rubber containing 25 mole percent styrene.

Two samples of the styrene-butadiene rubber were cross-linked following the procedure described in Example 16. In Example 17 the rubber was cross-linked with 20 parts of the terephthalaldehyde bis(p-toluenesulfonohydrazone) (described in Example 16) per 100 parts of rubber. The procedure was exactly the same as described in Example 16 except that the rubber was cured at a temperature of 200 C. The resulting vulcanizate had a percent gel of 92. The styrene-butadiene rubber of Example 18 was cross-linked with 25 parts of m-dibenzoylbenzene bis(p-toluenesulfonohydrazone) also following the procedure of Example 16 except that it was cured at a temperature of 200 C. The resulting vulca-nizate had a percent gel of 92.

Example 19 To a slurry of crystalline polypropylene in benzene was added sufiicient bis(wdiazopropionate) ester of 1,6- hexanediol dissolved in benzene to make a slurry containing 5 parts of diazo compound per 100 parts of polymer. The slurry was dried overnight at room temperature and the resulting powder pressed between steel plates at a temperature of C. and a pressure of 800 p.s.i. for 30 minutes. The film thus formed was substantially insoluble in hot decahydronaphthalene.

Example 20 To a solution of an ethylene-propylene copolymer, containing 32 mole percent propylene, in benzene was added sufi'icient bis(diazoacetate) ester of 1,10-decanediol to make a solution containing 10 parts of diazo compound per 100 parts of polymer. The solvent was removed under vacuum and the resulting mixture exposed to an ultraviolet light source under an atmosphere of nitrogen for one hour at a temperature of 20 C. Quartz equipment was used throughout the reaction. The resulting vulcanizate had a percent gel of 78.

' Example 21 To a slurry of crystalline polypropylene in benzene was added suificient bis(diazoacetate) ester of 1,10-decanediol dissolved in benzene to make a slurry containing 0.075 part of diazo compound per 100 parts of polymer. The slurry was dried overnight at room temperature and the resulting powder pressed between steel plates at a temperature of 175 C. and a pressure of 800 psi. for 30 minutes. The film thus formed was superior to polypropylene treated in the exact same way except for the addition of diazo compound, in higher density, greater strength and lower permeability to gases and liquids. Both the modified and unmodified samples dissolved in hot decahydronaphthalene. It can be seen from this example that poly(diazo) compounds can be used to impart improved properties to films without materially afiecting their solubility.

Example 22 A solution of 10 parts of terephthalaldehyde bis(ptoluenesulfonohydrazone) in dry dimethylformamide was prepared. To the solution was added 15 parts of sodium ethoxide and a bright yellow suspension formed. The suspension was added to a solution of 100 parts of polyisobutylene in toluene with agitation. The solvents were removed under vacuum and the resulting mixture was heated in a closed iron mold for one hour at a temperature of 180 C. The resulting vulcanizate was substantially insoluble in toluene.

Example 23 A sulfonamide precursor was prepared by reacting 2 moles of p-toluenesulfonyl chloride with 1 mole of 1,3- bis(aminomethyl)benzene in ethanol containing 2 moles of triethylamine. An ether solution of the intermediate bis (p-toluenesulfonamide) was treated with aqueous sodium nitrite (2 moles) and 10% sulfuric acid. The ether layer was separated, washed with dilute aqueous sodium carbonate and dried over magnesium sulfate. Removal of the ether and recrystallization of the yellow solid thus obtained yielded m-bis(N-nitroso-N-p-toluenesulfonyl-aminomethyl) benzene. It was analyzed for percent carbon, hydrogen and nitrogen. The results of the analysis are given below.

Found: C, 52.1%; H, 4.29%; N, 11.4%. C, 52.6%; H, 4.41%; N, 11.2%.

To a solution of an ethylene-propylene copolymer, containing 32 mole percent propylene, in benzene was added a sufficient amount of the precursor and potassium tert-butoxide to make a solution containing 10 parts of precursor and 5 parts of butoxide per 100 parts of polymer. The solvent was removed under vacuum and the mixture heated in a closed iron mold for 1 hour at a temperature of 190 C. under a pressure of 800 psi. The resulting vulcanizate was substantially insoluble in benzene.

What we claim and desire to protect by Letters Patent 1. The process of modifying a hydrocarbon polymer which comprises heating said polymer in admixture with from about 0.01% to about 20% based on the weight of the polymer of a poly(diazo) compound selected from the group consisting of IR! 1 fi) Ila! ACN2 and ACCN L x L 2 where x is an integer from 2 to 4, R is an organic radical inert to modification reactions, A is an aromatic radical inert to modification reactions, R is selected from the group consisting of hydrogen, alkyl, aryl and COOZ Calculated:

0 radicals where Z is selected from the group consisting of alkyl and aryl radicals and R is selected from the group consisting of hydrogen, alkyl and aryl radicals said heating being at the decomposition temperature of said poly(diazo) compound whereby chemical bonding is effected between the polymer molecules.

2. The process of modifying a hydrocarbon polymer which comprises irradiating said polymer under ultraviolet radiation in admixture with from about 0.01% to about 20% based on the weight of the polymer of a poly(diazo) compound selected from the group consisting of R! 0 RI! l 1 II I 1 AHCNZ and AOGN2 L X L F i t where x is an integer from 2 to 4, R is an organic radical inert to modification reactions, A is an aromatic radical inert to modification reactions, R is selected from the group consisting of hydrogen, alkyl, aryl and COOZ radicals where Z is selected from the group consisting of alkyl and aryl radicals and R is selected from the group consisting of hydrogen, alkyl and aryl radicals.

3. The process of claim 1 wherein the poly(diazo) compound is a diazoacetate ester of an alkane polyol.

4. The process of claim 3 wherein the diazoacetate ester is the bis(diazoacetate) ester of 1,6-hcxanediol.

5. The process of claim 3 wherein the diazoacetate ester is the bis(diazoacetate) ester of 1,10-decanediol.

6. The process of claim 1 wherein the poly(diazo) compound is p-bis(diazoacetyl) benzene.

7. The process of claim 1 wherein the poly(diazo) compound is m-bis(a-diazoethyl) benzene.

8. The process of claim 1 wherein the hydrocarbon polymer is cross-linked by said modification.

9. The process of modifying a hydrocarbon polymer which comprises heating said polymer in admixture with a base selected from the group consisting of alkali metal hydroxides, alkali metal alkoxides and alkaline earth oxides and from about 0.005% to about 25% based on the weight of the polymer of a poly(diazo) precursor selected from the group consisting of nitrosoureas, nitrosourethanes, N-nitroso derivatives of mesityl oxide-amine adducts, sulfonamides and bistoluenesulfonohydrazones which forms a poly(diazo) compound selected from the group consisting of l" :l i F" 1 "(1N2 and .A.C-CN3 L X L X where x is an integer from 2 to 100, R is an organic radical inert to modification reactions, A is an aromatic radical inert to modification reactions, R is selected from the group consisting of hydrogen, alkyl, aryl and COOZ radicals where Z is selected from the group consisting of alkyl and aryl radicals and R" is selected from the group consisting of hydrogen, alkyl and aryl radicals, said heating being at the decomposition temperature of said poly(diazo) compound whereby chemical bonding is effected between the polymer molecules.

10. The process of modifying a hydrocarbon polymer which comprises irradiating said polymer under ultraviolet radiation in admixture with a base selected from the group consisting of alkali metal hydroxides, alkali metal alkoxides and alkaline earth oxides and from about 0.005% to about 25 based on the weight of the polymer of a poly(diazo) precursor selected from the group consisting of nitrosoureas, nitrosourethanes, N- nitroso derivatives of mesityl oxide-amine adducts, sulfonamides and bis-toluenesulfonohydrazones which forms a poly(diazo) compound selected from the group consisting of where x is an integer from 2 to 100, R is an organic radical inert to modification reactions, A is an aromatic radical inert to modification reactions, R is selected from the group consisting of hydrogen, alkyl, aryl and COOZ radicals where Z is selected from the group consisting of alkyl and aryl radicals and R" is selected from the group consisting of hydrogen, alkyl and aryl radicals whereby chemical bonding is effected between the polymer molecules.

11. A hydrocarbon polymer modified by reacting with from about 0.005% to about 25% based on the weight of the polymer of a poly(diazo) compound selected from the group consisting of where x is an integer from 2 to 100, R is an organic radical inert to modification reactions, A is an aromatic radical inert to modification reactions, R is selected from the group consisting of hydrogen, alkyl, aryl and -COOZ radicals where Z is selected from the group consisting of alkyl and aryl radicals and R" is selected from the group consisting of hydrogen, alkyl and aryl radicals said reaction having been initiated by heating said polymer in admixture with said poly(diazo) compound at the decomposition temperature of said poly(diazo) compound so as to effect chemical bonding between the polymer molecules.

12. A hydrocarbon polymer modified by reacting with from about 0.005% to about 25 based on the weight of the polymer of a poly(diazo) compound selected from the group consisting of where x is an integer from 2 to 100, R is an organic radical inert to modification reactions, A is an aromatic radical inert to modification reactions, R is selected from the group consisting of hydrogen, alkyl, aryl and COOZ radicals where Z is selected from the group consisting of alkyl and aryl radicals and R" is selected from the group consisting of hydrogen, alkyl and aryl radicals said reaction having been initiated by irradiating said polymer in admixture with said poly(diazo) compound under ultraviolet radiation so as to effect chemical bonding between the polymer molecules.

13. The product of claim 11 wherein the hydrocarbon polymer is natural rubber.

14. The product of claim 11 wherein the hydrocarbon polymer is styrene-butadiene rubber.

15. The product of claim 11 wherein the hydrocarbon polymer is ethylene-propylene copolymer.

16. The product of claim 11 wherein the hydrocarbon polymer is polypropylene.

17. The product of claim 11 wherein the hydrocarbon polymer is polyethylene.

18. The product of claim 11 wherein the hydrocarbon polymer is polyisobutylene.

References Cited by the Examiner UNITED STATES PATENTS 2,469,819 5/1949 Flory et al 260-949 2,830,978 4/1958 Muller et a1. 26094.9 3,012,020 12/1961 Kirk et a1 260-94.9 3,058,944 10/1962 Breslow et a1 260-882 3,152,107 10/1964 Mullier et al. 26094.9

FOREIGN FATENTS 718,906 11/ 1954 Great Britain.

OTHER REFERENCES Journal of Organic Chemistry, vol. 21, pages 1013- v 1021, 1956. Also see C.A., 52, 1958, 7279-C.

JOSEPH L. SCHOFER, Primary Examiner.

I. A. SEIDLECK, Assistant Examiner. 

1. THE PROCESS OF MODIFYING A HYDROCARBON POLYMER WHICH COMPRISES HEATING SAID POLYMER IN ADMIXTURE WITH FROM ABOUT 0.01% TO ABOUT 20% BASED ON THE WEIGHT OF THE POLYMER OF A POLY(DIAZO) COMPOUND SELECTED FROM THE GROUP CONSISTING OF 